Patent GB-331822-A (GB)
Title: Improvements in the dyeing of regenerated cellulose materials
IPC: C09B35/26
Filed: 1929-04-05
Abstract: 331,822. Imperial Chemical Industries, Ltd., and Brightman, R. April 5,1929. Azo dyes.-Regenerated cellulose materials are dyed in level shades by means of the dyestuffs obtainable by coupling a tetrazotized mono or disulphonic acid of 4: 4<1>-diaminodiphenylurea with 2 mols. of a sulphonic or carboxylic acid derivative of a phenol, naphthol, naphthylamine, or N- substituted naphthylamine or with 1 mol. of such a component and 1 mol, of an aminonaphtholsulphonic acid or an N-substituted derivative thereof. The dyestuffs are also obtainable by other processes, e.g. (a) by coupling diazotized p-nitraniline-o-sulphonic acid or p-aminoacetanilide-o-sulphonic acid with a phenol, naphthol, or N-substituted naphthylamine, coupling 2 mols. of the diazo compounds with 1 mol. of such a component and 1 mol. of an N-substituted aminonaphtholsulphonic acid, reducing the nitro groups or hydrolyzing the acetylamÝno groups and treating the aminoazo compound or mixture of aminoazo compounds with phosgene, or (b) coupling 1 mol. of a diazotized unsulphonated nnitramine of the benzene series, such as pnitraniline or 5-nitro-2-anisidine, and 1 mol. of a diazotized sulphonated p-nitramine of the benzene series with 2 mols. of the same or different components as above specified, reducing the nitro groups. and treating the aminoazo compounds with phosgene. In an example viscose silk is dyed bluish red by treatment with the dyestuff obtained by coupling tetrazotized 4 : 4<1>-diaminodiphenylurea-3: 3'-disulphonic acid with 1 mol. of salicylic acid and 1 mol. of 2 : 8: 6-aminonaphthoisulphonic acid (coupled alkaline). A table is given showing the shades obtained on viscose silk by the use of various tetrazo components and various coupling components, other specified tetrazo components being the 2 :2<1>-disulphonic acid, 2-sulphonic acid, and 3-sulphonic acid of 4: 4'-diaminodiphenylurea, and 2-chloro- 4: 4<1>-diamino-5-methoxydiphenylurea - 3<1> - sulphonic acid, and other coupling components being 2: 3-oxynaphthoic acid, 1: 4-naphtholsulphonic acid, phenyl-2:8:.6-acid (coupled alkaline), benzoyl-2 : 8: 6-acid (coupled alkaline), and 1: 8. aminonaphthol-2 : 4-disulphonic acid (coupled alkaline). A second table shows the shades obtained on viscose silk with the dyestuffs resulting from the action of phosgene on the aminoazo compounds or mixtures of aminoazo compounds obtained by reducing the nitro groups of monoazo dyes of the type p-nitraniline or p-nitranilineo-sulphonic acid # salicylic acid, 1: 4-naphtholsulphonic acid, or phenyl-2 : 8: 6-acid (coupled acid). A third table shows the shades obtained on viscose silk with the dyestuffs resulting from the action of phosgene on the following mixtures of aminoazo compounds, (1) a mixture of the reduction product of the dyestuff 5-nitro- 2-anisidine # (acid) acetyl-2: 8: 6-acid and the hydrolysis product of the dyestuff 4-aminoacetanilide-2-sulphonic acid # 1 : 4-naphtholsulphonic acid, (2) a mixture of the hydrolysis product of the dyestuff 4-aminoacetanilide # 2: 6-naphtholsulphonic acid and the hydrolysis product of the dyestuff 4-aminoacetanilide-2- sulphonic acid # (alkaline) phenyl-2 : 8: 6. acid. Specifications 11766/01 and 21199/10 are referred to. 5. 4<1>-Diaminodiphenylurea-2-sulphonic acid is obtained by hydrolysis and reduction of the product from the action of phosgene or equimolecular proportions of p-aminoacetanilide and pnitraniline-o-sulphonic acid. 4: 4<1> - Diaminodiphenylurea-2 : 2<1>-disulphonic acid is obtained by reduction of the product from the action of phosgene on 2 mols. of p-nitraniline. o-sulphonic acid. 4: 4<1>-Diaminodiphenylurea-3-sulphonic acid is obtained by hydrolysis of the product from the action of phosgene on equimolecular proportions of p-aminoacetanilide-o-sulphonic acid and paminoacetanilide. 2-Chloro-4 : 4<1>-diamino-5-methoxydiphenylurea- 3<1>-sulphonic acid is obtained by hydrolysis of the product from the action of phosgene on equimolecular proportions of p-aminoacetanilide-o-sulphonic acid and 4-chloro-2-acetylamino-m-anisidine.